In recent years, along with miniaturization and multi-functionalization, portable electronic devices have various components densely arranged therein. Accordingly, a conductive gasket is used between an external housing and a built-in circuit board of a portable electronic device in order to reduce impact from the outside and also decrease electromagnetic waves penetrating into or leaking from the portable electronic device.
Also, a portable electronic device may include a plurality of antennas corresponding to functions due to multi-functionalization. At least some of the antennas may be built-in antennas and may be disposed on an external housing of the portable electronic device. Accordingly, a conductive contactor for providing electrical contact between an antenna disposed on the external housing and a built-in circuit board of the portable electronic device is used.
Also, recently, the adoption of a metal housing has been increasing in order to improve aesthetic impression and robustness thereof.
As a result, an electric path may be formed between the external housing and the built-in circuit board by a conductive gasket or a conductive contactor. In particular, as the metal housing and the circuit board form a loop, static electricity with high voltage may be instantaneously input through a conductor such as a metal housing having a large exposed surface area. In this case, the static electricity may be input into the built-in circuit board through the conductive gasket or the conductive contactor, thereby damaging the circuit such as an integrated circuit (IC).
Such a portable electronic device typically uses a charger to charge a battery. The charger rectifies external AC power to DC power and then transforms the DC power into low DC power suitable for the portable electronic device through a transformer. Here, in order to enhance electrical insulation of the transformer, a Y-CAP composed of capacitors is provided at both ends of the transformer.
However, when the Y-CAP does not have normal characteristics, such as in a case of a non-genuine charger or the like, DC power may not be sufficiently blocked by the Y-CAP. Furthermore, a leakage current may be generated by the AC power and may propagate along a ground part of the circuit.
The leakage current may be delivered even to a human-touchable conductor such as the external case of the portable electronic device. As a result, a user may feel an uncomfortable tingling sensation. In severe cases, the user may be injured by an electric shock accident.
Therefore, a protective element for protecting a user from the leakage current needs to be provided in the conductive gasket or the conductive contactor for connecting the metal housing and the circuit board.
Further, when the metal housing is used as an antenna, the conductive gasket or the conductive contactor needs to realize a high capacitance. This is because if the capacitance is low, signal attenuation occurs such that an RF signal is not smoothly delivered.
Thus, there is a need for a contactor having various functions for protecting a user or a circuit built in a portable electronic device as well as a simple electrical contact due to the use of a conductor such as a metal case.
However, additional components are needed to implement these various functions. Therefore, an additional space is required on a circuit board of a portable electronic device, which adversely affects miniaturization.
Such a functional contactor may maximize the area of the electrode in order to increase the capacitance of the functional element. In this case, when a contactor of a relatively small size is stacked on an electrode through soldering or when a functional element having the contactor stacked through soldering is mounted on a substrate through secondary soldering, the contactor is not fastened, and thus a failure occurs.
Also, generally, the contactor and the functional element are bonded to each other through soldering, and then the functional element having the contactor stacked thereon is bonded to the substrate through secondary soldering. In this case, a soldering part of the functional element and the contactor may be melted due to heat generated through the secondary soldering. Accordingly, a failure can occur in terms of adhesiveness, reliability, and the like of the contactor and thus may cause an electrical contact failure.